1. Technical Field
The present disclosure relates to a method of manufacturing a color filter substrate and a thin film transistor substrate, and more particularly, to a method of manufacturing a color filter substrate and a thin film transistor substrate used in a display apparatus.
2. Discussion of the Related Art
In fabricating a color filter substrate used for a thin film transistor liquid crystal display (TFT-LCD), a color filter layer including a red pixel, a green pixel and a blue pixel is formed. The color filter layer can be formed by a pigment dispersion technology. In the pigment dispersion technology, a photoresist containing a pigment is coated, exposed and developed. A post-bake is performed with respect to the photoresist to form a color filter having a certain color. Then the processes of coating, exposing, developing and post-bake of the photoresist are repeated such that color filters having various colors are sequentially formed.
However, the pigment dispersion technology is complex because the coating process, the exposing process, the developing process and the post-bake process are respectively performed with respect to the red, green and blue photoresist. In the pigment dispersion technology, the photoresist may be wasted because each photoresist is coated through a spin coating process, and then the photoresist is removed in the developing process.
A color filter layer can be formed by an inkjet printing technology. In the inkjet printing technology, a thick black matrix is formed by using an organic material, and color ink including a pigment and a solvent is sprayed through a nozzle by using the thick black matrix as a barrier. Then the solvent is removed.
The inkjet printing technology uses a smaller amount of materials as compared with the pigment dispersion technology.
However, with the inkjet printing technology, the barrier is used to prevent the overflow phenomenon of the color ink. To enhance the color reproducibility and to reduce the coupling phenomenon between pixels, the barrier having a high height is required. Thus, an organic black matrix that has a thickness of about 3 μm is used. However, when the organic black matrix has the thickness of about 3 μm, the exposure process and the pre-bake process are performed for an extended period of time due to the increased thickness of the organic black matrix. The extended period time of the exposure process and the pre-bake process to the black matrix can cause remnants, wrinkles and instability of a pattern to the black matrix.